Packing



HUGH T. STEWART, OF NEW YORK, N. Y ASSIGNDR TO ME TALASTIC INCL, OFJERSEY CITY, NEW JERSEY, A COBPORATIONUF NEW JERSEY. I

racnme.

ll'o Drawing.

This invention relates to packing such as may be used in variousmechanical devices for the purpose of sealing joints or connectionsbetween parts which may or may not have relative movement.-

An object of the invention is to provide an improved packing which whenused between relatively moving parts offers a minimum re-- tivit,whichis elastican plastic, and-which is re ativelyinexpesnsive. Otherobjects and advanta es will apparent from the following escription of apractical form of the invention and the novel features will be pointedout in claims.

Y The packing comprises lubricating oil, asbestos fibre, graphite, andbabbitt or other suitable anti -friction metal or alloy. Any suitablelubricating oil may be used but it 80 should preferably have a viscosityof not less than 30.0'and not more than 80.0 (Engler) at50 C. and notmore than 5.0 and less than 1.0 at 180 C. The specific gravity at 1 5 C.should not be less than .500 or more than .980 in order to obtain thebest results. The flash point should also preferably be above 200 C. andless than 350 C. in an open pan test. standard A.- C. transformer oilisa very satisfactory product for the oil component of the improvedpacking.

The asbestos fibre should be in the form of shreds, referably varyingfrom about 3 mm. in ength and 0.25 mmrin diameter to about 7 mm. inlength and 1.5 mm. in diameter.

The graphite, which forms a solid lubrican-t, should be finely dividedor co'mminuted', preferably in the form of flakes not larger than about2 mm. in diameter and 0.05 mm. in thickness. It has been found thatDixon ,#2 graphite proves very satisfactory as the graphite component ofthe packing.

. The metal or alloy component of the packing should be finely divided,such as in the It has been found that the by the action of a suitablecutting tool upon Application filed-July as, 1922. Serial in). 577,761.

forms of chips preferably not lar er than 5 mm in length, 3 mm. inwidth, an 0.5 mm. 1n thickness, and diminishing to pulverized form. Theslightly rough edges of the metallic chips enable the asbestos to holdthe chips 1n position. By the term chips l mean a form of particleswhich may be read- 11y obtained from commercial Babbitt metal, asdistinguished from particles which must be specially formed. The'chipsare obtained a piece of commercial Babbitt metal and the result is thatthe'chips are formedwith sharp edges which, when the chips are mixedwith the fibre, will help to shred the fibre.

The preferred proportions in which the components are mixed are asfollows, the portions being given by-weight:

, Parts. Asbestos 14 Oil 7' Metal Graphite 11 Any suitable metal oralloy may be used, but should preferably be babbitt, lead, or similarmetals or alloys. A very satisfactory anti-friction alloy for thispurpose is the following:

Tin 83.75% to 84.25%,copp'er 6.75%, antimony 8.75% to 9.25%, iron not'over 02%, lead not over .02%.

Any of the usual Babbitt metals mayalso be used. v

In the preferred preparation of the mixture, the carded asbestos fibreandoil are mixed and heated to about 100 'C.,'after which the babbitt isadded and mixed, then thegraphite. The temperature should always be lessthan the fusion temperature of the metal or alloy. After the componentmaterials. have been thoroughly mixed 'the may be cooled, and themixture is then ready for use. It has plasticity such that it can bepacked into any desired shape or size of cavlty. There is enoughelasticity when molded and compressed to cause it to fit closely to thepacked parts with an even pressure and maintain the close fit for anextended period. The graphite and oil form a superior lubricant formoving parts and the capillary action of the small particles draws oilcontinuously to the bearing surfaces. The oil also revents caking of thegraphite. The asestos, which is of itself of such a nature as M0 towithstand such chemical actionas' might by little without waste. The

venient, efiicient, durable, easi y and quickly applied and relativelyinexpensive.

removed from a stufiing box it may be easily v acking is conpulled apartand returned to its original loose condition. I j 1 p It will beunderstoodthat the proportions gi venherein are those which have beenfound to be the mostsatisfactory and that this is .for the purposeofexplaining the natureof the invention.

Obviously various minor changes .in proportions and equivalents of thecomponent arts or the manner of mixing may be ma e by those skilled inthe art within the principle and scope oithe inven tion. I

Iclaim: .1. A stufiing box packing material comprising fanintermixtureof small chips pf abbitt, comminu'ted ra hite, asbestos fibres,

and lubricating oil w ie has been heated to parts 7 comminuted graphite,14 parts of asbestos fibres, and 7 parts of lubricating oil, the prov toa temperature less than a temperature at material comatemperatur'eef'approximately 100 C. and

' less than the temperature at which the bab bitt fuses.

2; A stutfing box packingrmaterial com-,

prising an intermixture of approximately68 of small chips of babbitt, 11parts of portions being by weight.v 3. A stufling box packing prising anmtermixture oi babbitt chips,

prising an intermixture o graphite, asbestos fibres andlubricating oilin such" minor roportions that the resulting mass is loose mtexture.

4. A stufiing box packin material combabbitt chips.

acking is loose' non-com-- When,

' neeaeeo flake graphitefasbestos fibres and A. standard transformeroil. 1 r 5. The method of preparing a acking materialwhichcom'prises'heating as estos fibres and oil to approximately 100 C. thenadding 'babbitt chips and commiiiuted. graphite an mixm I 6. file methodof preparing a packing material which comprises mixing fibre and oil,addingw articles of anti-friction metal and mixing again, and thenadding a solid lubricant and mixin a ain.

.7. The metho o preparing a acking material which comprises mixing reand-oil, heating the'mixture to about 100 (1,,- adding particles ofvanti-friction metal and mixing again, and then adding a solid lubricantand mixiI iIgha-gain.

e method of preparing a packing material which comprises mixing fibreand oil, heating the mixture to about 100 0., adding particles ofanti-friction metal and mixing again, then adding a solid lubricant 'andmixing again, and maintaining the temperature -throughout'at less thanthe fusion temperature of the metal. 1

9. A loose packing material comprising a mixture ofchips ofanti-friction metallic material, fibre, graphite, and oil in such minorproportions that the resulting mass is loose in texture.

10. A stufling box packing material'comprising an intermixture ofsmall'chips. of babbitt, comminuted graphite, asbestos fibers, andlubricating oil Which has been preheated which the babbitt fuses in suchminor proper tions that the resulting mass is loose in texture.

In testimony whereof I have hereunto set my hand.

' HUGH T. STEWART. v

